:root{
  --bg:#f4f6fa; --panel:#ffffff; --panel-2:#fbfcfe; --ink:#16202e; --muted:#64748b;
  --line:#e2e8f0; --accent:#2563eb; --accent-soft:#e8efff;
  --easy:#0f9d76; --medium:#d97706; --hard:#dc2626;
  --ok:#0f9d76; --warn:#d97706; --err:#dc2626;
  --radius:12px; --shadow:0 1px 2px rgba(16,24,40,.06),0 8px 24px rgba(16,24,40,.06);
}
/* Light is the default. Dark is opt-in via the header toggle (data-theme="dark"). */
:root[data-theme="dark"]{
  --bg:#0e141c; --panel:#161d27; --panel-2:#1b232f; --ink:#e6edf6; --muted:#93a3b8;
  --line:#26303d; --accent:#5b9bff; --accent-soft:#1c2a42;
  --shadow:0 1px 2px rgba(0,0,0,.4),0 8px 24px rgba(0,0,0,.35);
}
*{box-sizing:border-box}
body{margin:0;background:var(--bg);color:var(--ink);
  font:15px/1.55 ui-sans-serif,system-ui,-apple-system,"Segoe UI",Roboto,sans-serif}
button,input,select,textarea{font:inherit;color:inherit}
a{color:var(--accent)}

/* ---------- chrome ---------- */
header.top{position:sticky;top:0;z-index:40;display:flex;align-items:center;gap:18px;
  padding:10px 18px;background:var(--panel);border-bottom:1px solid var(--line)}
.brand{font-weight:700;letter-spacing:-.2px;display:flex;align-items:center;gap:8px}
.brand small{font-weight:500;color:var(--muted)}
.spacer{flex:1}
#healthBtn.active{background:var(--accent-soft);color:var(--accent);border-color:transparent}

/* ---------- the numbered step bar ---------- */
.stepper{display:flex;align-items:center;gap:6px;flex-wrap:wrap;
  padding:12px 18px 0}
.stepper .stp{display:flex;align-items:center;gap:9px;background:none;border:0;
  padding:7px 14px 7px 8px;border-radius:999px;cursor:pointer;color:var(--muted);
  font-weight:600;font-size:14px}
.stepper .stp i{display:grid;place-items:center;width:24px;height:24px;border-radius:50%;
  background:var(--panel-2);border:1px solid var(--line);font-style:normal;font-size:13px}
.stepper .stp + .stp::before{content:"";width:26px;height:1px;background:var(--line);
  margin-right:9px;margin-left:-6px}
.stepper .stp.done{color:var(--ink)}
.stepper .stp.done:hover{background:var(--panel-2)}
.stepper .stp.done i{background:var(--accent-soft);border-color:transparent;color:var(--accent)}
.stepper .stp.here{background:var(--accent-soft);color:var(--accent)}
.stepper .stp.here i{background:var(--accent);border-color:transparent;color:#fff}
.stepper .stp.locked{opacity:.45;cursor:default}

/* ---------- step 2, how to build ---------- */
.method-cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(230px,1fr));gap:12px}
.method-card{display:flex;flex-direction:column;gap:7px;text-align:left;cursor:pointer;
  padding:16px;border:1px solid var(--line);border-radius:var(--radius);
  background:var(--panel-2);color:inherit}
.method-card:hover{border-color:var(--accent);background:var(--accent-soft)}
.method-card.on{border-color:var(--accent);background:var(--accent-soft)}
.method-card b{font-size:15px}
.method-card span{color:var(--muted);font-size:13px;line-height:1.5}

/* a form row that states a fixed fact instead of offering a choice */
.static-field{display:flex;flex-direction:column;gap:2px;padding:9px 12px;
  border:1px solid var(--line);border-radius:9px;background:var(--panel-2);color:var(--muted)}

/* ---------- the "i" help buttons ---------- */
.help{width:19px;height:19px;margin-left:8px;padding:0;border-radius:50%;cursor:pointer;
  border:1px solid var(--line);background:var(--panel-2);color:var(--muted);
  font:600 12px/1 ui-serif,Georgia,serif;vertical-align:middle}
.help:hover{border-color:var(--accent);color:var(--accent)}
.help.on{background:var(--accent);border-color:transparent;color:#fff}
.help-panel{margin:0 0 14px;padding:14px 16px;border:1px solid var(--line);
  border-radius:var(--radius);background:var(--panel-2)}
.help-panel dl{margin:0;font-size:13px;line-height:1.5}
/* "Term: what it does" on one line, the way a person would jot it down */
.help-panel dt{display:inline;font-weight:600}
.help-panel dt::after{content:":"}
.help-panel dd{display:inline;margin:0;color:var(--muted)}
.help-panel dd::after{content:"";display:block;height:6px}
.help-panel .hp{margin:0 0 10px;color:var(--muted);font-size:13px;line-height:1.55}
.help-panel .hp:last-child{margin-bottom:0}
.help-panel dl + .hp{margin-top:10px}
/* the cart is only 340px wide, so its panel needs to breathe less */
aside .help-panel{padding:11px 12px}
aside .help-panel dt{font-size:12.5px}
aside .help-panel dd,aside .help-panel .hp{font-size:12.5px}

/* ---------- back / next ---------- */
.wizard-nav{display:flex;align-items:center;gap:12px;padding:0 18px 40px;
  max-width:100%}
.top-stat{color:var(--muted);font-size:13px}

/* ---------- layout ---------- */
.layout{display:grid;grid-template-columns:270px minmax(0,1fr) 340px;gap:16px;
  padding:16px;align-items:start}
.pane{background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);
  box-shadow:var(--shadow)}
.pane.pad{padding:14px}
.sticky{position:sticky;top:66px;max-height:calc(100vh - 82px);overflow:auto}
h3.sec{margin:0 0 10px;font-size:12px;text-transform:uppercase;letter-spacing:.08em;color:var(--muted)}
.field{margin-bottom:14px}
label.lbl{display:block;font-size:12px;font-weight:600;color:var(--muted);margin-bottom:5px}
input[type=text],input[type=number],select,textarea{width:100%;padding:8px 10px;border-radius:9px;
  border:1px solid var(--line);background:var(--panel-2)}
input:focus,select:focus,textarea:focus{outline:2px solid var(--accent-soft);border-color:var(--accent)}
.chips{display:flex;flex-wrap:wrap;gap:6px}
.chip{border:1px solid var(--line);background:var(--panel-2);border-radius:999px;padding:5px 11px;
  cursor:pointer;font-size:13px;user-select:none}
.chip.on{background:var(--accent-soft);border-color:var(--accent);color:var(--accent);font-weight:600}
.chip.easy.on{background:#0f9d7622;border-color:var(--easy);color:var(--easy)}
.chip.medium.on{background:#d9770622;border-color:var(--medium);color:var(--medium)}
.chip.hard.on{background:#dc262622;border-color:var(--hard);color:var(--hard)}
.btn{display:inline-flex;align-items:center;gap:7px;justify-content:center;border:1px solid var(--line);
  background:var(--panel-2);border-radius:9px;padding:8px 13px;cursor:pointer;font-weight:600}
.btn:hover{border-color:var(--accent);color:var(--accent)}
.btn.primary{background:var(--accent);border-color:var(--accent);color:#fff}
.btn.primary:hover{filter:brightness(1.08);color:#fff}
.btn.danger:hover{border-color:var(--err);color:var(--err)}
.btn.wide{width:100%}
.btn.sm{padding:4px 9px;font-size:13px;border-radius:7px}
.btn:disabled{opacity:.5;cursor:not-allowed}
.row{display:flex;gap:8px;align-items:center}
.row.wrap{flex-wrap:wrap}
.muted{color:var(--muted)}
.small{font-size:13px}
.tiny{font-size:12px}

/* ---------- question cards ---------- */
.qcard{border:1px solid var(--line);border-radius:var(--radius);background:var(--panel);
  padding:14px;margin-bottom:12px;box-shadow:var(--shadow)}
.qcard.picked{border-color:var(--accent);box-shadow:0 0 0 1px var(--accent) inset}
.qhead{display:flex;align-items:center;gap:8px;flex-wrap:wrap;margin-bottom:9px}
.badge{font-size:11.5px;font-weight:700;padding:3px 8px;border-radius:999px;background:var(--panel-2);
  border:1px solid var(--line);color:var(--muted);white-space:nowrap}
.badge.easy{color:var(--easy);border-color:#0f9d7655}
.badge.medium{color:var(--medium);border-color:#d9770655}
.badge.hard{color:var(--hard);border-color:#dc262655}
.badge.key{color:var(--accent);border-color:var(--accent)}
.badge.id{font-family:ui-monospace,SFMono-Regular,Menlo,monospace;font-weight:600}
.stem{margin:2px 0 10px}
.stem img,.opt img{max-width:100%;border-radius:8px;background:#fff;padding:4px}
.opts{display:grid;grid-template-columns:1fr 1fr;gap:6px 14px}
@media (max-width:900px){.opts{grid-template-columns:1fr}}
.opt{display:flex;gap:8px;padding:5px 8px;border-radius:8px;border:1px solid transparent}
.opt .l{font-weight:700;color:var(--muted)}
.opt.correct{background:#0f9d7615;border-color:#0f9d7644}
.opt.correct .l{color:var(--easy)}
.qfoot{display:flex;gap:8px;align-items:center;flex-wrap:wrap;margin-top:10px;
  padding-top:10px;border-top:1px dashed var(--line)}
.expl{margin-top:8px;padding:9px 11px;background:var(--panel-2);border-radius:9px;font-size:14px}

/* ---------- bars ---------- */
.bar{height:9px;border-radius:999px;background:var(--panel-2);overflow:hidden;display:flex;
  border:1px solid var(--line)}
.bar i{display:block;height:100%}
.bar i.easy{background:var(--easy)} .bar i.medium{background:var(--medium)} .bar i.hard{background:var(--hard)}
.bar i.fill{background:var(--accent)}
.meter{margin-bottom:11px}
.meter .top{display:flex;justify-content:space-between;font-size:13px;margin-bottom:4px}
.meter.done .top b{color:var(--ok)}
.meter.over .top b{color:var(--err)}

/* ---------- misc ---------- */
.warn-list{margin:0;padding-left:16px}
.warn-list li{margin-bottom:4px;font-size:13px}
.lvl-error{color:var(--err)} .lvl-warn{color:var(--warn)} .lvl-ok{color:var(--ok)}
table.grid{width:100%;border-collapse:collapse;font-size:13.5px}
table.grid th,table.grid td{padding:7px 9px;border-bottom:1px solid var(--line);text-align:left}
table.grid th{color:var(--muted);font-size:12px;text-transform:uppercase;letter-spacing:.05em}
table.grid tr:hover td{background:var(--panel-2)}
.scroll{max-height:320px;overflow:auto}
.toast{position:fixed;right:18px;bottom:18px;z-index:100;background:var(--panel);border:1px solid var(--line);
  border-left:4px solid var(--accent);border-radius:10px;padding:11px 15px;box-shadow:var(--shadow);
  max-width:420px;white-space:pre-wrap}
.toast.err{border-left-color:var(--err)} .toast.ok{border-left-color:var(--ok)}
.modal-bg{position:fixed;inset:0;background:rgba(10,15,25,.55);z-index:90;display:flex;
  align-items:flex-start;justify-content:center;padding:40px 16px;overflow:auto}
.modal{background:var(--panel);border-radius:14px;box-shadow:var(--shadow);width:min(940px,100%);padding:20px}
.grid2{display:grid;grid-template-columns:1fr 1fr;gap:14px}
.grid4{display:grid;grid-template-columns:repeat(4,1fr);gap:12px}
@media (max-width:1100px){.layout{grid-template-columns:1fr}.sticky{position:static;max-height:none}
  .grid4,.grid2{grid-template-columns:1fr 1fr}}
.kpi{background:var(--panel-2);border:1px solid var(--line);border-radius:10px;padding:11px 13px}
.kpi b{display:block;font-size:22px;line-height:1.2}
.pill-list{display:flex;flex-wrap:wrap;gap:6px}
.hidden{display:none}
.chapter-row{display:flex;align-items:center;gap:8px;padding:4px 0;border-bottom:1px solid var(--line)}
.chapter-row .nm{flex:1;font-size:13.5px}
.chapter-row input[type=number]{width:62px;padding:4px 6px}
.slider-row{display:flex;align-items:center;gap:10px;margin-bottom:6px}
.slider-row input[type=range]{flex:1}
.slider-row span{width:52px;text-align:right;font-size:13px;color:var(--muted)}